DRYING OF CHILI PEPPER (CAPSCIUM FRUTSCENS)

Abstract

ABSTRACT Drying is one of the common methods of food preservation and is carried out on untreated/unblanched and treated/blanched chili pepper using sun, solar and hot‐air drying. The drying curves generated from the three methods showed that drying of treated/blanched pepper was faster than that of untreated/unblanched pepper. The drying rate period observed for all the methods and samples was the falling rate drying regime. This suggests that the blanching pretreatment assisted water loss and thus decreased the resistance to water loss at the surface of the product. The drying time of the dried pepper varied from 27 h for hot‐air drying to 144.5 h for sun drying respectively. The values of moisture diffusivity coefficient ranged from 2.163 × 10−9 m2/s for hot‐air drying to 1.125 × 10−9 m2/s for sun drying.PRACTICAL APPLICATIONSA common method of preserving pepper, a vegetable with versatile use, is drying and this is done by sun, solar and oven‐drying methods. Climatic variations of sun and solar drying make it unsuitable for large‐scale production. Hot‐air drying is thus considered as an alternative drying method because it decreases drying time and improves the hygienic quality of the dried product. Pretreating pepper by blanching increases its rate of drying. The effect of each drying method on the drying rate, equilibrium moisture content and moisture diffusivity coefficient were used to compare the drying methods. Hot‐air drying had the lowest drying time whereas pretreated samples also dried faster. The effective moisture diffusivity of oven dried samples as well as pretreated samples were highest. This indicates that oven drying reduces drying time and can be used to dry pepper samples for large‐scale production.